1. Field of the Invention
This invention relates to a vehicle audio adapter for switching between a genuine head unit and a commercially available non-genuine head unit in an electromultivision system provided in a vehicle.
2. Description of the Related Art
An electromultivision is a system including a color multidisplay capable of displaying navigation screens, vehicle information such as time of maintenance, an operating state of air conditioner, an operating state of audio equipment, and a TV screen when a vehicle is idling. When a touch panel on the display is touched or when nearby switches are operated, the operating state of each above-mentioned apparatus is set or switched. The above-mentioned apparatuses include respective microcomputers and are connected into a network so that a room LAN is constructed.
In the foregoing system, even when the audio equipment or navigation system is replaced with a commercially available non-genuine equipment without communicating function adapted to the room LAN, the consistency of the system is lost. As a result, since the other apparatuses in the LAN are turned off, the audio equipment or navigation system cannot be replaced with the commercially available equipment.
Therefore, an object of the present invention is to provide an audio adapter which can be used when the genuine head unit is replaced with a commercially available non-genuine head unit or the adapter is switched between the genuine head unit and the non-genuine head unit in uses and which can simplify the work for replacing the genuine head unit with the non-genuine one or for adding the non-genuine head unit.
To achieve the object, the present invention provides a vehicle audio adapter which is used in a vehicle multivision system in which electronic apparatuses including an audio, television, car navigation, air condition control, picture monitor and switch panel are connected by a LAN cable thereby to be constructed into a room LAN so that the electronic apparatuses are intensively controlled by a single monitor. In the vehicle audio adapter, when a predetermined one of the electronic apparatuses connected by the LAN cable is replaced with a non-genuine apparatus which cannot be connected by the LAN cable and is unsuitable for the room LAN, functions of the room LAN are maintained with the genuine apparatus being left and the genuine apparatus is replaceable with the non-genuine apparatus.
According to the above-described adapter, when a predetermined one of the electronic apparatuses connected by the LAN cable is replaced with a non-genuine apparatus which cannot be connected by the LAN cable and is unsuitable for the room LAN, functions of the room LAN are maintained with the genuine apparatus being left and the genuine apparatus is replaceable with the non-genuine apparatus.
In a first preferred form, an apparatus necessary for the room LAN is moved from one position to another in the vehicle and which further comprises a fitting for mounting the non-genuine apparatus instead of the moved room LAN. The non-genuine apparatus is installed by a fitting at a position where an apparatus necessary for the room LAN has been moved to another position.
In a second preferred form, the non-genuine apparatus added at another position in the interior of the vehicle can be replaced without moving an apparatus necessary for the room LAN. The non-genuine apparatus added to another position in the interior of the vehicle can be switched without moving an apparatus necessary for the room LAN.
In a third preferred form, the vehicle audio adapter further comprises a signal wire provided for connecting a LAN cable or extension cable required for moving the apparatus necessary for the room LAN. The signal wire connects the adapter to a middle of the LAN cable or extension cable provided for moving the apparatus necessary for the room LAN.
In a fourth preferred form, a sound signal circuit is connected only when the non-genuine apparatus is turned on, using an external amplifier remote signal changing to 12 V when the non-genuine apparatus is turned on and to 0 V when the non-genuine apparatus is turned off.
In a fifth preferred form, the adapter further comprises a double-throw switch with a plurality of poles or relay switch for switching the audio signal circuit between the genuine audio apparatus and a non-genuine audio apparatus.
In a sixth preferred form, another location in the vehicle to which an apparatus required for the room LAN is moved includes an interior of a glove box, a space under a seat, an interior of a trunk, a luggage space and the like. In this case, the adapter further comprises fittings for fixing the apparatus at said another location.